.demo{ background: #ffffff; }

.main-timeline{
    overflow: hidden;
    position: relative;
}

.main-timeline:before{
    content: "";
    width: 3px;
    height: 100%;
    background: #000;
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
}

.main-timeline .timeline{
    width: 50%;
    float: left;
    position: relative;
}

.main-timeline .timeline:before,
.main-timeline .timeline:after{
    content: "";
    display: block;
    width: 100%;
    clear: both;
}

.main-timeline .timeline:before{
    content: "";
    width: 45%;
    height: 3px;
    background: #000;
    position: absolute;
    top: 50%;
    right: 0;
    transform: translateY(-50%);
}

.main-timeline .year{
    display: block;
    width: 120px;
    height: 120px;
    line-height: 120px;
    border-radius: 50%;
    background: #e3bd40;
    font-size: 30px;
    font-weight: bold;
    color: #fff;
    text-align: center;
    position: absolute;
    top: 50%;
    right: 7%;
    transform: translateY(-50%);
}

.main-timeline .timeline-content{
    width: 65%;
    padding: 40px;
    background: #e3bd40;
    position: relative;
}

.main-timeline .timeline-content:after{
    content: "";
    border-bottom: 40px solid #23363a;
    border-left: 40px solid transparent;
    position: absolute;
    bottom: 20px;
    right: 20px;
}

.main-timeline .title{
    font-size: 19px;
    font-weight: bold;
    color: #fff;
    margin: 0 0 10px 0;
}

.main-timeline .title a{
    font-size: 19px;
    font-weight: bold;
    color: #fff;
    margin: 0 0 10px 0;
}

.main-timeline .description{
    font-size: 14px;
    color: #fff;
    margin: 0;
}

.main-timeline .timeline:nth-child(2n):before{
    right: auto;
    left: 0;
}

.main-timeline .timeline:nth-child(2n) .year{
    right: auto;
    left: 7%;
}

.main-timeline .timeline:nth-child(2n) .timeline-content{ float: right; }

.main-timeline .timeline:nth-child(2){ margin-top: 160px; }

.main-timeline .timeline:nth-child(odd){ margin: -160px 0 0 0; }

.main-timeline .timeline:nth-child(even){ margin-bottom: 70px; }

.main-timeline .timeline:first-child,
.main-timeline .timeline:last-child:nth-child(even){ margin: 0; }

.main-timeline .timeline:nth-child(2n) .year,
.main-timeline .timeline:nth-child(2n) .timeline-content{ background: #ff6cba; }

.main-timeline .timeline:nth-child(3n) .year,
.main-timeline .timeline:nth-child(3n) .timeline-content{ background: #60bee4; }

.main-timeline .timeline:nth-child(4n) .year,
.main-timeline .timeline:nth-child(4n) .timeline-content{ background: #a3cc42; }


.main-timeline .timeline:nth-child(5n) .year,
.main-timeline .timeline:nth-child(5n) .timeline-content{ background: #ff0000; }



@media only screen and (max-width: 1200px){
    .main-timeline .year{
        width: 100px;
        height: 100px;
        line-height: 100px;
    }
}

@media only screen and (max-width: 990px) and (min-width: 768px){
    .main-timeline .year{
        width: 80px;
        height: 80px;
        line-height: 80px;
        font-size: 24px;
    }
}

@media only screen and (max-width: 767px){
    .main-timeline:before,
    .main-timeline .timeline:before{ display: none; }
    .main-timeline .timeline,
    .main-timeline .timeline:nth-child(even),
    .main-timeline .timeline:nth-child(odd){
        width: 100%;
        float: none;
        text-align: center;
        margin: 0;
    }
    .main-timeline .timeline{ margin-bottom: 20px !important; }
    .main-timeline .timeline:last-child{ margin-bottom: 0 !important; }
    .main-timeline .year,
    .main-timeline .timeline:nth-child(2n) .year{
        margin: 0 auto 10px;
        position: relative;
        top: 0;
        left: 0;
        transform: translateY(0);
    }
    .main-timeline .year:after{
        content: "";
        width: 3px;
        height: 20px;
        background: #fff;
        position: absolute;
        bottom: -20px;
        left: 50%;
        z-index: 1;
        transform: translate(-50%);
    }
    .main-timeline .timeline .timeline-content{
        width: 100%;
        float: none;
        padding: 40px;
    }
    .main-timeline .timeline .timeline-content:before{
        content: "";
        border-bottom: 40px solid #23363a;
        border-right: 40px solid transparent;
        position: absolute;
        bottom: 20px;
        left: 20px;
    }
}